1. Field of the Invention
The present invention relates to a toner cartridge for use in an image forming apparatus such as a copying machine, a facsimile or a printer, and to an image forming apparatus in which the toner cartridge is mounted.
2. Description of the Related Art
In an image forming apparatus such as a copying machine, a facsimile or a printer, a toner cartridge functions to supply toner to a developing device and is detachably mounted in the image forming apparatus. The toner cartridge is detachably mounted in order to enable a user himself/herself to perform a replacing operation when toner in the toner cartridge runs short.
From the standpoint of product management and print quality, manufacturers of image forming apparatuses list up some recommendable toner cartridges for use. If a toner cartridge with low quality is used, the print quality may deteriorate or, in some cases, a failure may occur in the image forming apparatus.
However, there are many kinds of toner cartridges, and the toner cartridges have similar shapes. It is thus difficult for a user to visually discriminate toner cartridges. Under the circumstances, there is a demand for a method of discriminating toner cartridges, without depending on the user's experience or senses.
A conventional toner cartridge comprises a toner container which contains toner, a shutter which opens/closes a discharge port that is formed in the toner container, and a cap which closes a filling port that is formed in the toner container. An end portion of the toner cartridge, at which the discharge port is formed, receives a driving force from a cartridge holder that is disposed in the image forming apparatus. Thereby, the toner cartridge is rotated at a predetermined speed.
In usual cases, the toner container is formed of, e.g. polyethylene (PE) by blow molding. The blow molding is suited to manufacturing of hollow articles, and the cost of blow molding is low. Thus, the blow molding is a manufacturing method suitable for toner containers which are consumable components. However, the processing precision of the blow molding is low, and non-uniformity may, in some cases, occur in the dimensional precision of finished toner containers.
If the dimensional precision of a toner cartridge is low, such a case may occur that a toner cartridge, which does not correspond to the version, point of destination, etc. of the image forming apparatus, would be mounted in the image forming apparatus by application of a strong force.
Even if the toner cartridge is mounted, if the toner cartridge does not correspond to the version, point of destination, etc. of the image forming apparatus, a number of failures may occur due to the difference in shape between the toner cartridge and the cartridge holder. For example, if the position and size of the discharge port of the toner cartridge do not correspond to the cartridge holder, toner which is discharged from the toner cartridge may leak to the surrounding part. Moreover, if the outer shape of a to-be-inserted part of the toner cartridge does not correspond to the cartridge holder, a part of the toner cartridge may contact the cartridge holder, resulting in peeling of a seal member that is provided on the toner cartridge or cartridge holder.